Chaeles e



(No Model.)

0. R. MEAD.

LATHE CHUCK. No. 372,482. Patented Nov. 1, 1887.

WITNESSES: INVENTOR a. a 7 w w. m $633M WHY, $4M M ATTORNEYS.

N. FETER$ Phom-Ulhagraplwr, wmin lon. D. c.

UNITED STATES ATENT Fries.

CHARLES R. MEAD, OF ONEIDA, NEW YORK.

LATH E-CHUCK.

Application filed February 28, 1887. Serial No. 229,159. (No model.)

To all whom it may concern:

Be it known that 1, CHARLES It. MEAD, of Oneida,in the county of Madisomin the State of New York, have invented new and useful Improvements in Lathe-Ohucks, of which the following, taken in connection with the accompanying drawings, is a full, clear, and exact description.

This invention has special reference to the chuck for which I have obtained Letters Patent of the United States No. 321,740, dated July 7, 1885. In the use of said chuckIhave found some difficulty in retaining the jaws thereof in their gripping positions, owing to the capability of the jaw-carrying portion of the chuck-head of rotating on the rear section thereof.

The object of my present invention is to obviatc said defect and to render the chuck more effective in general; and to that end the invention consists in the improved construction and combination of parts, as hereinafter fully described, and specifically set forth in the claims.

In the accompanying drawings, Figure 1 is a side view of my improved chuck. Fig. 2 is a longitudinal section of the same, taken in a plane parallel with the axis of two of thejaws. Fig. 3 is a face view. Fig. 4 is a detached rear-end View of the front section of the head, showing the cranks of the jaws and the adjusting-screw, and Fig. 5 is a detached plan view of the camgrooved plate by which the cranks of thejaws are turned.

Similar letters of reference indicate corresponding parts.

D and D represent, respectively, the front and rear sections of a transverselydivided chuck-head, which sections are detachably yet firmly secured to each other, so as to compel them to turn in unison. The frontseetion,D, is formed with a central cavity, 0, which eX- tends from the rear end of said section for ward and is terminated by an annular flange, 10,011 the face end of the front section. In the rear portion of the front section, I), is rigidly secured a ring, 9', and this ring and the aforesaid flange n are provided with coinciding eyes, in which the jaws A A A are pivoted eccentrically. Back of the ring 1' are cranks b I), which are rigidly attached to or formed integral with the rear journals of the jaws.

The rear section, D, is provided with an annular groove, 0, in the end adjacent to the front section, and 011 said end of the rear section is pivoted an annular plate, I, having an annular flange, t, entering the groove 22 and forming therewith the pivot of the said plate. This plate is provided with the segmental eanrgrooves aaa,into which project the wristpins of the cranks b b, and the engagement of these parts causes the jaws to be turned on their axes and to move toward and from the center of the chuck by the turning of the plate I.

The edge of the plate I is provided with a screw-threaded groove, Z, with which engages the adjusting-screw O, which is journaled in grooves in the adjacent ends of the hcadsections D D and shouldered therein, so as to prevent the screw from moving longitudinally. By turning this screw the plate I receives rotary motion, and by the engagement of the cranks b b with the cam-grooves a a a of the aforesaid plate the jaws A A A are turned on their axes and caused to move either toward or from the center of the chuck, as before stated.

Having described my i11vention,whatI claim as new, and desire to secure by Letters Patent, 1s-

1. The combination of the chuck-head, cccentrieally-pivoted jaws, and cranks on said jaws, the rotatable plate I, provided with segmental cam-grooves a a a and with a screwthreaded groove, Z, in its edge, and the adjusting-screw, O, journaled in the head and engaging the plate I, substantially as described and shown.

2. The combination of the chuck-head divided transversely and having the two sections rigidly secured to each other, and the front section formed with a central cavity extending from the rear end of said section forward and terminated by an annular flange, a, on the face end of the front section, the ring 1', secured to the rear portion of the interior of the front section, the jaws A A. A, pivoted eccentrically in the aforesaid flange and ring and provided with the cranks b I) I), the annular plate I, pivoted in the head and provided withthe cam-grooves a a a and with the screwthreaded groove Z, and the adjusting-screw O, journaled in the head and engaging the plate 5 I, substantially as described and shown.

3. In combination with the front section, D, and the jaws A A A, pivoted eccentrically therein and provided with the cranks b b b, the rear section, D, rigidly secured to the [0 front section and provided with the annular groove 12, the annular plate I, provided with cam-grooves a a a, engaging the aforesaid cranks and formed with the annular flange t, 

